Files
certigo/verify.go
T

92 lines
2.2 KiB
Go

/*-
* Copyright 2016 Square Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package main
import (
"crypto/x509"
"fmt"
"io/ioutil"
"os"
"strings"
)
func caBundle(caPath string) *x509.CertPool {
if caPath == "" {
return nil
}
bundleBytes, err := ioutil.ReadFile(caPath)
if err != nil {
fmt.Fprintf(os.Stderr, "error reading CA bundle: %s\n", err)
os.Exit(1)
}
bundle := x509.NewCertPool()
bundle.AppendCertsFromPEM(bundleBytes)
return bundle
}
func verifyChain(certs []*x509.Certificate, dnsName, caPath string) {
intermediates := x509.NewCertPool()
for i := 1; i < len(certs); i++ {
intermediates.AddCert(certs[i])
}
opts := x509.VerifyOptions{
DNSName: dnsName,
Roots: caBundle(caPath),
Intermediates: intermediates,
}
chains, err := certs[0].Verify(opts)
if err != nil {
red.Printf("Failed to verify certificate chain:\n")
fmt.Printf("\t%s\n", err)
return
}
green.Printf("Server certificates appear to be valid (found %d chains):\n", len(chains))
for i, chain := range chains {
names := []string{}
for _, cert := range chain {
var name string
if cert.Subject.CommonName != "" {
name = cert.Subject.CommonName
} else {
name = fmt.Sprintf("Serial #%s", cert.SerialNumber.String())
}
if isSelfSigned(cert) {
name += green.SprintfFunc()(" [self-signed]")
}
for _, alg := range badSignatureAlgorithms {
if cert.SignatureAlgorithm == alg {
name += red.SprintfFunc()(" [%s]", alg.String())
break
}
}
names = append(names, name)
}
fmt.Printf("[%d] %s\n", i, strings.Join(names, "\n\t=> "))
}
}
func isSelfSigned(cert *x509.Certificate) bool {
return cert.CheckSignatureFrom(cert) == nil
}